lg(250/2.5)=lg100=lg10^2=2lg10=2
1) 120/1.25=96
2) (120+96)×0.8=172.8
3) (120+96+172.8)/3=129.6
<span>x</span>² <span>+ 3x</span>⁴ = х²(1 + 3х²)<span>;
3a</span>² <span>- 27 = 3(а</span>² - 9) = 3(а - 3)(а + 3)<span>;
2x + 4 + x</span>² <span>+ 2x = 2(х + 2) + х(х + 2) = (х + 2)( 2 + х) = (х + 2)</span>²<span>;
Решите уравнение:
X</span>² <span>- 3x = 0
х(х - 3) = 0
х = 0 или х - 3 = 0
х = 3
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